Method and a cassette holder for performing x-ray examination

ABSTRACT

In connection with X-ray or like examination there is used a cassette holder arrangement which is carried by a frame structure (7) by means of pivotal arms (4) which are capable of being swung in the horizontal plane, such as to adjust the position of the cassette in the vertical direction. The arrangement enables pictures to be taken of a sitting patient in mutually perpendicular directions, with the aid of a radiation source (2). The cassette holder (3) can be swung between the exposure positions in a circuit path around the sitting patient, by activation of one of the arms (4). To this end there can be used a parallel linkage (11) which is operative to guide the cassette holder during this pivotal movement. the cassette holder is fixated relative to one of the arms (4), by means of a locking device (8), which is released when wishing to pivot the cassette holder. The invention also relates to a cassette holder arrangement of the aforedescribed kind.

FIELD OF INVENTION

The present invention relates to a method for carrying out X-rayexaminations or like examinations with the aid of a cassette-carriedreceptor intended to receive radiation from a radiation source which isadapted to take two or more exposures.

The invention also relates to a cassette-holder device for carrying outsuch diagnostics.

Particular problems are encountered, both on the part of the patient andon the part of the personnel, when subjecting to X-ray examinationelderly patients, who are often seriously handicapped, and othercategories of patients who have difficulty in leaving their hospital bedon their own feet, e.g. because of serious illness or injury sustainedin a traffic accident for instance. In some cases it is necessary toX-ray a patient at the beside with the patient in bed, requiring theimage receptor to be placed between the patient and the mattress, withall the drawbacks associated therewith.

Bedside examinations are carried out both in intensive care wards, usingportable X-ray equipment, and in the X-ray department itself.

The majority of patients who are either too ill or too weak to standunsupported or unaided are, nevertheless, able to sit on the edge of thebed. Although some lung X-ray frames will permit frontal pictures to betaken from the bed, no room is available for side pictures, since thelung frame is normally placed adjacent a wall which makes it impossibleto turn the bed through an angle of 90°.

BACKGROUND ART

Various methods and cassette holders have been proposed with theintention of facilitating the X-ray examination of handicapped patients.

For instance, U.S. Pat. No. 4,468,803 (Ronci) describes acassette-holder suspension system which enables the cassette holder tobe rotated in mutually different planes so as to enable different typesof exposures to be taken. This known system include a clamping devicewhich is maneuvered with the aid of knobs and by means of which thecassette holder and carrier means can be brought to different desiredpositions, for instance adjacent a table. Vertical adjustments can bemade only by releasing the clamping device and mounting said device atthe height desired. One drawback with this known apparatus is that it isheavy to manipulate, particularly when moving the apparatus betweendifferent positions of application.

U.S. Pat. No. 2,651,725 (McFarland) describes a similar cassette holderdevice which can be mounted in different positions adjacent a patient'sbed. Adjustments require the manipulation or activation of a relativelylarge number of clamping or tightening members which--as a rule--arelocated at considerable distance from one another.

Other examples of the known art are found described in U.S. Pat. No.3,795,815 (Weinstock et al.), which teaches a cassette holder fitted toa wheel chair and SE,B,354 728 (Tidestrom et al.) which teaches a freelytransportable device for holding an X-ray film cassette in freelyvariable positions.

The majority of known arrangements and apparatus have the drawback thata cassette provided with receptor and mounted in a cassette holder canbe centered in relation to the radiation source connected only withgreat difficulty. For instance, it is difficult to position theradiation source in relation to the image receptor so that radiationemitted from said source will pass at right angles to the receptor.Consequently, there is an obvious risk that the images taken will beunsatisfactory and need to be retaken, with subsequent exposure of thepatient to unnecessary high dosages of radiation.

These difficulties are accentuated when a grid or screen is placed inthe vicinity of the cassette holder--as is normally the case. Animportant prerequisite with respect to satisfactory images orphotographs is that the screen extends perpendicularly to the radiationbeam in one plane.

SUMMARY OF THE INVENTION

The object of the present invention is to provide a method and anarrangement which will avoid the majority of the aforesaid drawbacksencountered with known methods and arrangements in respect of themajority of handicapped patients who are unable to leave their bedsunaided but who, nevertheless, are able to assume a sitting position inbed, possibly with the assistance of attending personnel.

The inventive method is of the kind defined in the preamble of thefollowing claim 1 and is characterized by the features set forth in thecharacterizing clause of said claim.

The inventive method enables various types of images to be taken withoutnoticeable discomfort to the patient and without impediment to movementof the cassette holder between different, relevant setting positions.Precise centering of the receptor in relation to the radiation source isalso achieved, and only negligible adjustments to the position orattitude of the patient are needed, these adjustments being easilymanaged by the attendant personnel. The small positional changesrequired are more related to exposures to be taken with patients ofdifferent sizes.

Another small movement normally required of a patient is related to thenecessity of taking an exposure with the patient leaning slightlyforwards. The patient can straighten his/her back slightly, when thecassette holder is passed in the aforesaid circuit path between thevarious exposure positions.

The automatic guiding of the cassette holder can be effected with theaid of a parallel linkage mechanism which is mounted in an appropriatemanner in relation to the cassette holder and the attachment of saidpivotal arm or arms and which will provide the movement desired.

The cassette-holder may be self-locking on the end of the pivotal arm orarms, i.e. so as to ensure that the position to which the cassetteholder is adjusted will remain unchanged until a force of given value isapplied.

It is preferred in practice, however, that the cassette holder isfixated in a desired position of adjustment with the aid of afinger-operated fixating device which is released prior to commencementof said pivotal movement.

According to a second aspect, the invention also relates to acassette-holder device for X-ray or like examination, saidcassette-holder device having the characteristic feature set forth inthe following claim 3.

An exemplifying embodiment of the invention will now be described withreference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a cassette-holder device constructed inaccordance with the invention, and shows the device is coaction with aradiation source for the exposure of an X-ray picture on a bed-sittingpatient.

FIG. 2 is a view from above of the holder device illustrated in FIG. 1.

FIG. 3, finally, is a perspective view of a holder device and radiationsource according to FIG. 1 when taking a side-exposure of the patient,i.e. in a direction which is 90° to the direct shown in FIG. 1.

DESCRIPTION OF PREFERRED EMBODIMENTS

The reference numeral 1 in the various Figures of the drawingsidentifies a cassette-holder device for X-ray or like examination. Thecassette-holder device is intended for coaction with a radiation source2 carried by a telescopic, ceiling-mounted frame 10.

The cassette-holder itself is referenced 3 and comprises a so-calledpotter or bucky box which is intended to receive replaceably and tocenter with receptor-equipped cassettes of mutually different sizes.

The cassette holder 3 is mounted on an upper and a lower pivotal arm 4,each of said arms being pivotally connected at one end thereof to arespective holder element 5 extending from a central slot 7a in a columnstructure 7.

The holder elements 5 form part of a counter-balanced hoist arrangementwhich enables the cassette holder device to be positioned in thevertical direction.

The outer ends of respectively pivotal arms 4 are connected to thecassette holder, approximately in the center of said holder, by means ofa pivot axle 4b.

The cassette holder can be releasably locked in desired positionsrelative to the arms 4, with the aid of a locking device in the form ofa knob 8.

Extending perpendicularly from the lower side of the cassette holder 3is a shoulder 6 which is connected to the lower element 5 projectingfrom the column structure 7, by means of a parallel linkage 11. Theparallel linkage 11 is connected to respective elements 5 and 6 viapivot axles 5a and 6a respectively. The parallel linkage 11 therewithforms a parallel mechanism which is operative to guide the cassetteholder in a predetermined path upon activation of one of the pivotalarms 4 between the two positions illustrated in chain lines in FIGS. 1and 2 and forming an angle of 90° with one another.

The position of the cassette holder illustrated in FIGS. 1 and 2, wheresaid holder is parallel with the wall, can be said to constitute a"parking position", i.e. a position in which the cassette holder is outof the way.

A conventional exposure position for taking a photograph of the lungs ofa sitting patient 15 is shown in full lines in FIGS. 1 and 2. Thepatient is shown seated in a forwardly inclined position.

The cassette holder is then moved to the position illustrated in FIG. 3for taking a side picture, by activation of the arm 4. In doing so, thelocking knob 8 is first released, so that the arm 4 can be swung. Theparallel linkage mechanism 11 assists in enabling the cassette holder tobe moved in a circuit path around the patient 15, to the positionillustrated in FIG. 3, i.e. without discomfort to the patient.

As illustrated in FIG. 3, the cassette holder is provided with a handleor hand grip 16. The patient grips the handle, as shown in FIG. 3, sothat the patient will be brought to a correct position in relation tothe image receptor concerned, more or less automatically. It may benecessary, in this respect, for the patient to adjust his/her positionslightly, in order to enable a picture of the best possible quality tobe taken. The X-ray operator assists the patient in making thesemovements, which can therewith can be performed without unduedifficulty.

When the cassette holder has been brought to the position illustrated inFIG. 3, the knob 8 is turned so as to lock the cassette in its adjustedposition.

The handle 16 is removably attached to the cassette holder, and can beremoved when not needed.

I claim:
 1. A method for performing X-ray examination with the use of acassette-carried receptor intended to receive radiation from a radiationsource which is set to take two or more pictures of a patient inexposure positions in at least approximately perpendicular directions,said cassette being detachably received in a holder which is carried bya frame structure and which can be adjusted positionally in a verticaldirection, characterized by pivotally mounting the cassette holder onthe end of one or more pivotal arms which can be swung in the horizontalplane; and activating said pivotal arm or arms such as to move thecassette holder between the various exposure positions whileautomatically guiding the holder in a circuit path past a sittingpatient.
 2. A method according to claim 1, characterized by releasablylocking the cassette holder to the pivotal arm in said exposurepositions.
 3. A cassette holder device for X-ray examination with theaid of a cassette-carried receptor intended for receiving radiation froma radiation source (2), said cassette being removably located in aholder (3) which is carried by carrier means (4) on a frame structure(7) for vertical adjustment in relation to said frame structure,characterized in that the carrier means includes at least one arm (4)which can be pivoted in the horizontal plane and which is pivotallyconnected at one end thereof to the cassette holder (3) so that whentaking pictures in at least approximately perpendicular directions on asitting patient (15), it can be moved between the exposure positions ina circuit path past the patient.
 4. A cassette holder device accordingto claim 3, characterized in that the cassette holder (3) is carried byan upper and a lower arm (4) which engage approximately centrally withtwo mutually opposing sides of the cassette holder (3).
 5. A cassetteholder device according to claim 4 characterized by means (8) forreleasably locking the cassette holder in relation to one of the arms(4).
 6. A cassette holder device according to claim 3, characterized bya parallel linkage (11) which is operative to guide the cassette holder(3) in said path when the arm (4) is pivoted.
 7. A cassette holderdevice according to claim 3, characterized by a detachably mountedelement (16) on the cassette holder by means of which the cassetteholder can be gripped by said patient while an exposure is taken.
 8. Acassette holder device according to claim 3, characterized by an elementmounted on the cassette holder by means of which the cassette holder canbe gripped by said patient while an exposure is taken.